@@ -1,3 +1,8 @@
+2012-02-20 David S. Miller <firstname.lastname@example.org>
+ * config/sparc/sparc.md (load_pcrel_sym<P:mode>): Explain why we
+ don't use the "rd %pc" instruction on v9 for PIC register loads.
2012-02-20 Aldy Hernandez <email@example.com>
@@ -1352,6 +1352,10 @@
;; Load in operand 0 the (absolute) address of operand 1, which is a symbolic
;; value subject to a PC-relative relocation. Operand 2 is a helper function
;; that adds the PC value at the call point to register #(operand 3).
+;; Even on V9 we use this call sequence with a stub, instead of "rd %pc, ..."
+;; because the RDPC instruction is extremely expensive and incurs a complete
+;; instruction pipeline flush.
[(set (match_operand:P 0 "register_operand" "=r")